1. Field of the Invention
This invention relates to basketball backboard mounting assemblies having variable height adjustment means.
2. Description of Related Art
Basketball hoops mounted on backboards are normally supported from above at a height of ten feet. This height is formidable for shorter players and almost impossible for children. Adjustable-height backboard support units which permit the basket hoop to be lowered to say eight feet, are in use at school gymnasiums, YMCA's and like places. Those adjustable units known to Applicant require on-site assembly and installation, usually on a pair of vertical round tubes mounted from a ceiling structure and assembly, to be made at site, including a second pair of tubes from which backboard support brackets project forwardly. A crank-type linear adjustment screw raises and lowers the height-adjustable assembly relative to the fixed members.
In one prior art unit the first pair of round ceiling-mounted tubes have open lower ends into which are inserted a pair of internal tubes which telescope slidingly upward within the fixed tubes. From the lower ends of the interior telescoping tubes, brackets extend forward to a third pair of tubes from which forward-projecting brackets are used to mount the backboard. The upper ends of the third pair of tubes have ring-like slides which slide along the outer wall of the fixed tube.
An inherent weakness in these height-adjustable support mechanisms, besides the inconvenience of assembling them on site, and the frequent maintenance required to tighten the various components, is the fact that sideward forces applied to the basketball hoop or backboard cause the brackets which project forward from the slidable tubes to deflect angularly. While this angular deflection is resisted by the backboard itself, out-of-plane stresses are imposed on the backboard, which may in time damage it. Since the tubes are round, this problem is not alleviated by increasing their diameter or wall thickness.